Bug 1701796: Move IsTouchDeviceSupportPresent to LookAndFeel remoting to prevent win32k usage in the content process. r=emilio,geckoview-reviewers,owlish

Differential Revision: https://phabricator.services.mozilla.com/D123497

dom/events/TouchEvent.cpp

@@ -9,12 +9,12 @@
 #include "mozilla/dom/Touch.h"
 #include "mozilla/dom/TouchListBinding.h"
 #include "mozilla/BasePrincipal.h"
+#include "mozilla/LookAndFeel.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/StaticPrefs_dom.h"
 #include "mozilla/TouchEvents.h"
 #include "nsContentUtils.h"
 #include "nsIDocShell.h"
-#include "mozilla/WidgetUtils.h"
 
 namespace mozilla::dom {
 
@@ -194,29 +194,16 @@ bool TouchEvent::PrefEnabled(JSContext* aCx, JSObject* aGlobal) {
   return PrefEnabled(docShell);
 }
 
-// static
-bool TouchEvent::PlatformSupportsTouch() {
-#if defined(MOZ_WIDGET_ANDROID)
-  // Touch support is always enabled on android.
-  return true;
-#elif defined(XP_WIN) || defined(MOZ_WIDGET_GTK)
-  static bool sDidCheckTouchDeviceSupport = false;
-  static bool sIsTouchDeviceSupportPresent = false;
-  // On Windows and GTK3 we auto-detect based on device support.
-  if (!sDidCheckTouchDeviceSupport) {
-    sDidCheckTouchDeviceSupport = true;
-    sIsTouchDeviceSupportPresent =
-        widget::WidgetUtils::IsTouchDeviceSupportPresent();
-    // But touch events are only actually supported if APZ is enabled. If
-    // APZ is disabled globally, we can check that once and incorporate that
-    // into the cached state. If APZ is enabled, we need to further check
-    // based on the widget, which we do below (and don't cache that result).
-    sIsTouchDeviceSupportPresent &= gfxPlatform::AsyncPanZoomEnabled();
-  }
+static bool PlatformSupportsTouch() {
+  // Touch events are only actually supported if APZ is enabled. If APZ is
+  // disabled globally, we can check that once and incorporate that into the
+  // cached state. If APZ is enabled, we need to further check based on the
+  // widget, which we do in PrefEnabled (and don't cache that result).
+  static bool sIsTouchDeviceSupportPresent =
+      !!LookAndFeel::GetInt(LookAndFeel::IntID::TouchDeviceSupportPresent) &&
+      gfxPlatform::AsyncPanZoomEnabled();
+
   return sIsTouchDeviceSupportPresent;
-#else
-  return false;
-#endif
 }
 
 // static

dom/events/TouchEvent.h

@@ -94,7 +94,6 @@ class TouchEvent : public UIEvent {
                       bool aMetaKey, TouchList* aTouches,
                       TouchList* aTargetTouches, TouchList* aChangedTouches);
 
-  static bool PlatformSupportsTouch();
   static bool PrefEnabled(JSContext* aCx, JSObject* aGlobal);
   static bool PrefEnabled(nsIDocShell* aDocShell);
   static bool LegacyAPIEnabled(JSContext* aCx, JSObject* aGlobal);

widget/LookAndFeel.h

@@ -342,6 +342,9 @@ class LookAndFeel {
     /** The horizontal scrollbar height, in CSS pixels. */
     SystemHorizontalScrollbarHeight,
 
+    /** A boolean value to determine whether a touch device is present */
+    TouchDeviceSupportPresent,
+
     /*
      * Not an ID; used to define the range of valid IDs.  Must be last.
      */

widget/WidgetUtils.cpp

@@ -14,12 +14,6 @@
 #include "nsIStringBundle.h"
 #include "nsTArray.h"
 #include "prenv.h"
-#ifdef XP_WIN
-#  include "WinUtils.h"
-#endif
-#ifdef MOZ_WIDGET_GTK
-#  include "mozilla/WidgetUtilsGtk.h"
-#endif
 
 namespace mozilla {
 
@@ -97,16 +91,6 @@ nsIntRect RotateRect(nsIntRect aRect, const nsIntRect& aBounds,
 
 namespace widget {
 
-uint32_t WidgetUtils::IsTouchDeviceSupportPresent() {
-#ifdef XP_WIN
-  return WinUtils::IsTouchDeviceSupportPresent();
-#elif defined(MOZ_WIDGET_GTK)
-  return WidgetUtilsGTK::IsTouchDeviceSupportPresent();
-#else
-  return 0;
-#endif
-}
-
 // static
 void WidgetUtils::SendBidiKeyboardInfoToContent() {
   nsCOMPtr<nsIBidiKeyboard> bidiKeyboard = nsContentUtils::GetBidiKeyboard();

widget/WidgetUtils.h

@@ -79,11 +79,6 @@ class WidgetUtils {
                                          uint32_t* aUnshiftedCharCode,
                                          uint32_t* aShiftedCharCode);
 
-  /**
-   * Does device have touch support
-   */
-  static uint32_t IsTouchDeviceSupportPresent();
-
   /**
    * Send bidi keyboard information to content process
    */

widget/android/nsLookAndFeel.cpp

@@ -376,6 +376,11 @@ nsresult nsLookAndFeel::NativeGetInt(IntID aID, int32_t& aResult) {
       aResult = 25;
       break;
 
+    case IntID::TouchDeviceSupportPresent:
+      // Touch support is always enabled on android.
+      aResult = 1;
+      break;
+
     default:
       aResult = 0;
       rv = NS_ERROR_FAILURE;

widget/gtk/nsLookAndFeel.cpp

@@ -29,6 +29,7 @@
 #include "mozilla/AutoRestore.h"
 #include "mozilla/Telemetry.h"
 #include "mozilla/ScopeExit.h"
+#include "mozilla/WidgetUtilsGtk.h"
 #include "ScreenHelperGTK.h"
 #include "nsNativeBasicThemeGTK.h"
 
@@ -872,6 +873,9 @@ nsresult nsLookAndFeel::NativeGetInt(IntID aID, int32_t& aResult) {
       aResult = 1;
       break;
     }
+    case IntID::TouchDeviceSupportPresent:
+      aResult = WidgetUtilsGTK::IsTouchDeviceSupportPresent() ? 1 : 0;
+      break;
     default:
       aResult = 0;
       res = NS_ERROR_FAILURE;

widget/nsXPLookAndFeel.cpp

@@ -108,7 +108,7 @@ static EnumeratedCache<FontID, widget::LookAndFeelFont, FontID::End> sFontCache;
 //
 // This needs to be of the same length and in the same order as
 // LookAndFeel::IntID values.
-static const char sIntPrefs[][42] = {
+static const char sIntPrefs[][43] = {
     "ui.caretBlinkTime",
     "ui.caretBlinkCount",
     "ui.caretWidth",
@@ -175,6 +175,7 @@ static const char sIntPrefs[][42] = {
     "ui.allPointerCapabilities",
     "ui.systemVerticalScrollbarWidth",
     "ui.systemHorizontalScrollbarHeight",
+    "ui.touchDeviceSupportPresent",
 };
 
 static_assert(ArrayLength(sIntPrefs) == size_t(LookAndFeel::IntID::End),

widget/windows/nsLookAndFeel.cpp

@@ -591,6 +591,9 @@ nsresult nsLookAndFeel::NativeGetInt(IntID aID, int32_t& aResult) {
           static_cast<int32_t>(widget::WinUtils::GetAllPointerCapabilities());
       break;
     }
+    case IntID::TouchDeviceSupportPresent:
+      aResult = WinUtils::IsTouchDeviceSupportPresent() ? 1 : 0;
+      break;
     default:
       aResult = 0;
       res = NS_ERROR_FAILURE;